Download (v3)
Version 3 adds a Growl confirmation when the password is successfully copied.
Download (v2)
Generate a random password (alpha-numeric, mixed case) and automatically copy it to your clipboard.
Usage

> password
Uses default length of 12

> password 10
Creates a 10 character password
> password 12 strong
Creates a 12 character password with some special characters
> password 16 stronger
Creates a 16 character password with more special characters
Download (v1)
Version 1 requires you to specify a length and does not provide ‘strong’ and ‘stronger’ options.
> password 10
Where ’10′ is how many characters the password should be

You can download Alfred App for free here: http://www.alfredapp.com/.
To kick things up a notch with extensions and more, get the Powerpack for Alfred.

Any chance you’d like to add generating passwords from http://passphra.se/ to this? Very cool plugin